First of all, you will have to apply through an email provided on their job post. Your CV and Cover Letter will be reviewed within some days, after which you will be invited for a video interview session with them if found suitable.
However, you will be informed on the course of your interview, that if successful, you will have to come over to Thailand for a one week training (usually) - every traveling bills and miscellaneous expenses on the visa preparation will be taken care of by them. But they would like to confirm you will be willing and eligible to travel from your said country of residence without any crime issue hindering the process.
From Thailand, you will be taught on how they operate their sales business on textiles and what they are expecting from you. You will also have time to explore their tourist and amusement parks for personal experience - a way of creating a comfortable working environment for you.